Active Water-Wave Absorber
Active Water-Wave Absorber
Matthew Carney
ME236: Control & Optimization of Distributed Parameters Professor Alex Bayen University of California, Berkeley 04.30.2007
UC Berkeley, Spring 2007 1
Contents
• • • • • • Motivation Initial Idea Literature Search Focus Current Work Future Work www.emec.org.uk UC Berkeley, Spring 2007
2
Motivation
• Significant amounts of energy is stored in the ocean
• Large potential for extracting energy from waves
• Control is the key to optimizing energy extraction and economic feasibility.
www.epri.com/oceanenergy
UC Berkeley, Spring 2007
3
Initial Idea
• 1-Degree of Freedom Point Absorber • Direct Drive Linear Generator • Optimize Hydrodynamic Parameters
– Added Mass – Added Damping
• Optimize Phase Control
UC Berkeley, Spring 2007 4
Literature Search
• Eriksson, M., Isber, J., Leijon, M. “Hydrodynamic Modeling of a Direct-Drive Wave Energy Converter.” International Journal of Engineering Science, vol. 43, pages 1377-1387, 2005. Falnes, Johannes “Ocean Waves and Oscillating Systems: Linear Interactions Including Wave-energy Extraction.” Cambridge University Press, Cambridge. 2002. Havelock, T. H., “Forced Surface-Waves on Water.” Philosophic Magazine of Science, vol. 8, no. 51, Oct. 1929. Milgram, Jerome H., “Active Water-Wave Absorbers.” Journal Fluid Mechanics, vol. 43, part 4, pages 845-859, 1970. Yeung, Ronald W. “Added Mass and Damping of a Vertical Cylinder in Finite-depth Waters.” Applied Ocean Research, vol. 3, no. 3, pages 119-133. 1981.
•
• • •
UC Berkeley, Spring 2007
5
Focus
• Simplify the Problem!
• “To absorb a wave means to generate a wave or, in other words: To destroy a wave is to create a wave.” – Johannes Falnes
UC Berkeley, Spring 2007 6
(2D Wave-Maker) -1
Active Water-Wave Absorbers Jerome H. Milgram Journal of Fluid Mechanics (1970), vol. 43, pp. 845-859
S
x y θ
C
D p
-∞
h
d
UC Berkeley, Spring 2007
7
Formulation
Matthew Carney
ME236: Control & Optimization of Distributed Parameters Professor Alex Bayen University of California, Berkeley 04.30.2007
UC Berkeley, Spring 2007 1
Contents
• • • • • • Motivation Initial Idea Literature Search Focus Current Work Future Work www.emec.org.uk UC Berkeley, Spring 2007
2
Motivation
• Significant amounts of energy is stored in the ocean
• Large potential for extracting energy from waves
• Control is the key to optimizing energy extraction and economic feasibility.
www.epri.com/oceanenergy
UC Berkeley, Spring 2007
3
Initial Idea
• 1-Degree of Freedom Point Absorber • Direct Drive Linear Generator • Optimize Hydrodynamic Parameters
– Added Mass – Added Damping
• Optimize Phase Control
UC Berkeley, Spring 2007 4
Literature Search
• Eriksson, M., Isber, J., Leijon, M. “Hydrodynamic Modeling of a Direct-Drive Wave Energy Converter.” International Journal of Engineering Science, vol. 43, pages 1377-1387, 2005. Falnes, Johannes “Ocean Waves and Oscillating Systems: Linear Interactions Including Wave-energy Extraction.” Cambridge University Press, Cambridge. 2002. Havelock, T. H., “Forced Surface-Waves on Water.” Philosophic Magazine of Science, vol. 8, no. 51, Oct. 1929. Milgram, Jerome H., “Active Water-Wave Absorbers.” Journal Fluid Mechanics, vol. 43, part 4, pages 845-859, 1970. Yeung, Ronald W. “Added Mass and Damping of a Vertical Cylinder in Finite-depth Waters.” Applied Ocean Research, vol. 3, no. 3, pages 119-133. 1981.
•
• • •
UC Berkeley, Spring 2007
5
Focus
• Simplify the Problem!
• “To absorb a wave means to generate a wave or, in other words: To destroy a wave is to create a wave.” – Johannes Falnes
UC Berkeley, Spring 2007 6
(2D Wave-Maker) -1
Active Water-Wave Absorbers Jerome H. Milgram Journal of Fluid Mechanics (1970), vol. 43, pp. 845-859
S
x y θ
C
D p
-∞
h
d
UC Berkeley, Spring 2007
7
Formulation